7/28/2019 TasNat 1925 No1 Vol2 Pp9-11 Rodway TasmanianFerns
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THE TASMANIAN NATURALISTthen get caught by the wind and
gra-duaJIy moved further from high water mark.In time, sufficient
accumulates to form asandy beach; and if the wind is strong,sand
dunes begin to grow. High cliffsare usually separated by fine
beaches. Onsuch a cuast el'OEIion is active. I f currenk; run
strongly and indentationsH bound, the best beaches will be found.I
i the prevailing winds are inshore youwill find high sand dunet'!o
l'hu5 thestormy \ V e ~ t Coast preBents Ub Tasmania'sfinest
beaches, and the rugged South-Easthas many good ones; while the
relativelyquiet waters of Bass Strait an-d D'Entre
C i l ~ t r e a n x Channel leave us with low rockcoasts and few
stretches of sand.The numerous "tied-islands," or pairs ofi.slallus
connected by a narrow sand spitthat abound round out coast, e.g.,
MariaIsland. Brm.y, South Arm, Tasman'sPeninsula, probably have
their origin
likewise, in the droJ)ping of sedimente bythe tide and currents
as they are checkedwhen passing th e two islands.Wind piles up th e
sand into dunes toa certain height; but unless protected thesame
wind tends to blow the top sandlayers off these dunes when they
havereached a certain height. Thus th e dunescontinually tend to
move inland, oftenspreading destruction over many miles ofcountry,
The danger to th e railway linenear Strahan &rom overwhelming
dunes isa case in point. The only thing to chet:kthe onward march
of th e sand dunes isvegetation. 'Many pleasant fields havebeen
ruined by remo\,.-.-ing vegetation nearthe seashore. Cutting trees
or burninggrass on a sand dune is as much d crime,and likely to be
fraught with as dangerousresults of the lighting of wanton bushf i
r e ~ described earlier. A. N. Lewis.
Some Tasmanian FernsIt does not require a person to be abotanist
in order to be interested ID theform of a fern. Though they bea r
nobeautiful flowers nor offer any ag)'t-eable fruits, thel'13 is
somc,thing in th:
gracefulness of foliage which appeals tothe sense of even the
indifferent passrrby. To the stUdent there is a muchgrentf:r
attra,ction; there is recalled tohis mind the time when the
ancestorsof the ferns of the present day coveredthe earth with a
mighty vegetation. fUiug up the marshy depressions with the: ~ p e
n t spore caRes and decaying lunbs tomake the coal seams of the
presentgelleration. There were then no flowering plants, no other
trees but primitiveforms related to the conifers, then theern:s.
Their relatives, the clUb mOB-ses,grew to noble dimensions of a
hundredfeet and more stimulated by the warmhumid atmosphere then
obtaining.Few scenes in nature can be morebeautiful than a fern
gully. \Vith a background of shrubs and trees th e Old ~ l a l
ltree ferns spread their long fronds filliug up every spa-ce where
the light of thesun may enter, Though the complete
Mosaic of these Frondsmay appear as though they must absorb
every particle of light energy fallingabout them, yet beneath this
canopy1:\ f' the plant beings of greatest interestto th e
naturalist. Delicate filmy ferns ofmany forms, beautiful names and
weirdfungi revel in the fern trunks and moists('il of the depths of
the gully, We al l
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note tbe beauty, but how few eal'e toknow more; yet a further
acquaintaneewith the structure and life of ferns wi IIadll so much
pleasure to a walk inbush that the little amount of
thinkingl'equired will amply repay us.
Take the Old Man fern, which ap-peal'S by Its robustness as
though Itn l 1 ~ 8 t live throughout the world, aidedin this
ambitious delSil'e by the number Jfspares it customarily sheds. for
in t l 1 1 ~case of :;he average tree fern theseamount to about
fifty million per annum, yet it s distribution appears to bevery
restricteu. I t occurs in many partstemperate Australia, also ill
New Zealand, but nowhere as luxuriqntly as']'asmania.
Yes, th e average tree fern, after it hascome to maturity, drops
from it s frondlSH, fewer than fifty millions of spores, anyone of
which may, i f circumstances faVOl' it , eventually grow into an
Old Manhee fern itself, But how many of thesefifty millions do
really succeed't Examinethe average gully with perhaps a hundl'ed
specimens, there are a few thous1-:nd young ones looking quite
happy; outof these a few may re,ach th e stage of
b E g i ~ n i n g to form a trunk, but veryfe,,,' mdeed appear
to 'Succeed in pushingup their heads, afterA Hundred Years of
Effort,
t ~ k e up a position of maturity amongstIts fellows. Perhaps on
the average not
